This application claims the priority of German Patent Applications DE 102 13 098.1, filed Mar. 23, 2002, and DE 102 48 697. 2, filed Oct. 18, 2002, which are incorporated herein by reference.
The invention relates to a cartridge, comprising a cartridge case and a projectile, wherein the cartridge case contains a propellant charge igniter that extends in the direction of the longitudinal axis of the cartridge and wherein an electrically programmable projectile fuse is arranged inside the projectile. The projectile fuse is connected via at least one electrical line to an electrode on the cartridge base.
In the field of military technology, particularly relating to large-caliber ammunition, explosive ammunition with a programmable timed fuse is expected to have its maximum effectiveness in front of and above the target. The timed fuse must therefore be supplied with the respective data. If the data supply is intended to increase the flexibility of the tank crew in the loaded state, e.g. for switching between the various operating modes of the fuse and/or for effecting a subsequent change in the time signal even after the loading operation, the ammunition must have an electrical connection between the cartridge base and the fuse. The ammunition is then contacted via the tank system and the respective electronic guide systems.
In the case of a galvanic connection between the cartridge base and the projectile fuse, the loading operation and the installation of electrical lines must meet high requirements. In particular, with ammunition having a cartridge base that can be turned relative to the projectile head (as is the case for the Leopard 2 ammunition), it must be ensured that the electrical connecting lines cannot tear as a result of turning or that the naturally existing point of intersection of the lines is not interrupted.
Among other things, the electrical line provided inside the ammunition must meet the following requirements:
low costs/low expenditure;
installation so as to permit the loading operation;
trouble-free data and energy transfer;
ability of the electrical line to rotate;
prevention of axial or radial forces from being exerted upon the propellant charge igniter;
elastic absorption of axial or radial displacements;
EMC stability;
avoidance of long cable remnants on the propellant charge igniter following the firing, thus guaranteeing sufficient protection for the crew;
avoidance of long cable remnants on the guide assembly following the separation, thus avoiding external ballistic interference;
protection of the electrical line against powder dust; and
avoidance of cable remnants inside the weapon barrel.
German Patent reference DE 100 52 741 A1 discloses a cartridge of the aforementioned type, for which the electrical connection in the region between the front end of the propellant charge igniter and the projectile tail section involves a rigid connector assembly, thus forming two conductor sections. The first conductor section that is connected to the cartridge base and extends along the propellant-charge igniter in the front-end region of the propellant charge igniter has a spiral design to improve the safety against rotation of the electrical line.
The disadvantages of the known cartridge include, among other things, an involved protection for the spirally wound cable (large space required), as well as a rigid connector assembly that does not permit a theoretically xe2x80x9cinfinitexe2x80x9d turning of the two conductor sections relative to each other. In addition, the electrical line is very long, thus resulting in final ballistic interference of the projectile and endangerment of the tank personnel during the cartridge ejection after the ammunition is fired. Finally, it requires a time-consuming installation of the electrical line through the opening in the cartridge case on the side facing the projectile.
A cartridge of the aforementioned type with a programmable projectile fuse is furthermore known from reference DE 101 02 624 A1. This cartridge is provided on the front of the propellant charge igniter with a contact element in the form of a connector that is connected via a first conductor section extending through the propellant charge igniter to the electrode on the cartridge base. On the propellant charge igniter side facing the contact element, the projectile is provided with a bonnet or cowl-shaped receptacle that encloses the contact element and contains at least one bushing or sleeve-type contact, which has an electrically conducting connection to the projectile fuse via a second conductor section extending inside the projectile. To join the two conductor sections, the bushing-type contact element is fitted during the projectile assembly onto the plug-type contact element associated with the propellant charge igniter.
The fact that the production of the plug-in contacts and the bushing-type contacts is relatively involved is a further disadvantage of the cartridge. In addition, a bonnet that supports itself on the projectile tail section is required for accommodating the bushing-type contact. Finally, the connector assembly can be subject to extreme stresses during the projectile assembly, causing the plug-in contact to break off or the bonnet to be bent.
It is the object of the present invention to provide a cartridge of the aforementioned type wherein the electrical line to be inserted between the cartridge base and the projectile fuse can be installed easily and does not tear, not even following numerous projectile rotations relative to the cartridge base.
This object generally is achieved by the invention, according to which a cartridge comprises a cartridge case including a cartridge base, a projectile, a propellant charge igniter extending in the direction of the longitudinal axis of the cartridge and arranged inside the cartridge case, an electrically programmable projectile fuse arranged in the projectile, and at least one electrical line connecting the projectile fuse to an electrode arranged on the cartridge base, and wherein
the cartridge case includes at least first and second case sections that are arranged axially one behind the other and are joined, with the first case section being connected to the cartridge base and extending to a front end of the propellant charge igniter, and the second case section being connected to the projectile, the projectile having a tail portion that extends to near an end of the second case section that faces the first case section;
the electrical line has a first rotating connector assembly in a region between a front end of the propellant charge igniter and the projectile tail portion, so that a first conductor section of the electrical line, which is arranged inside or on the outside of the propellant charge igniter, can be turned relative to a second conductor section that is arranged on the projectile; and
a spring element arranged on the projectile tail portion, which acts upon the second conductor section and biases the second conductor section with a predetermined force toward the projectile tail portion.
Additional and particularly advantageous embodiments of the invention are disclosed and discussed.
According to the invention, the cartridge case consists of at least two parts, with at least one separation location in the region between the front end of the propellant charge igniter and the projectile tail. During the installation of the electrical lines, suspended sections of the cartridge case are joined in such a way that short ends of two conductor sections can be connected just prior to the final assembly using a gap between the suspended case sections and an inherently rotatable connector. The rotatable connector is attached to the propellant charge igniter and has a connection to one of the conductor sections that is oriented at an angle to the axis of rotation of the rotatable connector. This orientation provides a better transfer of the rotational movement and takes up the smallest possible space. The space between case sections required for ammunition loading is accommodated by attaching at least one suitable spring element, e.g. a spirally wound spring plate, to one of the conductor sections. At the same time, it is ensured that the conductor sections connected to the case sections respectively have short lengths. Following the loading operation, the spring element retracts the electrical line to a protected and locally fixed position. The required structural space is kept small enough that the connector assembly is protected against erosion and powder dust with a suitable bonnet-type element (protective element) of elastic material.
The above-mentioned requirements for the electrical signal line can be met with the aid of the invention.
Further details and advantages of the invention follow from the exemplary embodiments explained below with the aid of drawing figures.